New Problem Solution "Add to Array-Form of Integer"

README.md

@@ -8,6 +8,7 @@ LeetCode
 
 | # | Title | Solution | Difficulty |
 |---| ----- | -------- | ---------- |
+|989|[Add to Array-Form of Integer](https://leetcode.com/problems/add-to-array-form-of-integer/) | [C++](./algorithms/cpp/addToArrayFormOfInteger/AddToArrayFormOfInteger.cpp)|Easy|
 |988|[Smallest String Starting From Leaf](https://leetcode.com/problems/smallest-string-starting-from-leaf/) | [C++](./algorithms/cpp/smallestStringStartingFromLeaf/SmallestStringStartingFromLeaf.cpp)|Medium|
 |987|[Vertical Order Traversal of a Binary Tree](https://leetcode.com/problems/vertical-order-traversal-of-a-binary-tree/) | [C++](./algorithms/cpp/verticalOrderTraversalOfABinaryTree/VerticalOrderTraversalOfABinaryTree.cpp)|Medium|
 |986|[Interval List Intersections](https://leetcode.com/problems/interval-list-intersections/) | [C++](./algorithms/cpp/intervalListIntersectons/IntervalListIntersections.cpp)|Medium|

algorithms/cpp/addToArrayFormOfInteger/AddToArrayFormOfInteger.cpp

@@ -0,0 +1,62 @@
+// Source : https://leetcode.com/problems/add-to-array-form-of-integer/
+// Author : Hao Chen
+// Date   : 2019-03-25
+
+/***************************************************************************************************** 
+ *
+ * For a non-negative integer X, the array-form of X is an array of its digits in left to right order. 
+ *  For example, if X = 1231, then the array form is [1,2,3,1].
+ * 
+ * Given the array-form A of a non-negative integer X, return the array-form of the integer X+K.
+ * 
+ * Example 1:
+ * 
+ * Input: A = [1,2,0,0], K = 34
+ * Output: [1,2,3,4]
+ * Explanation: 1200 + 34 = 1234
+ * 
+ * Example 2:
+ * 
+ * Input: A = [2,7,4], K = 181
+ * Output: [4,5,5]
+ * Explanation: 274 + 181 = 455
+ * 
+ * Example 3:
+ * 
+ * Input: A = [2,1,5], K = 806
+ * Output: [1,0,2,1]
+ * Explanation: 215 + 806 = 1021
+ * 
+ * Example 4:
+ * 
+ * Input: A = [9,9,9,9,9,9,9,9,9,9], K = 1
+ * Output: [1,0,0,0,0,0,0,0,0,0,0]
+ * Explanation: 9999999999 + 1 = 10000000000
+ * 
+ * Note：
+ * 
+ * 	1 <= A.length <= 10000
+ * 	0 <= A[i] <= 9
+ * 	0 <= K <= 10000
+ * 	If A.length > 1, then A[0] != 0
+ * 
+ ******************************************************************************************************/
+
+class Solution {
+public:
+    vector<int> addToArrayForm(vector<int>& A, int K) {
+        int carry = K;
+        for (int i = A.size() - 1; i >= 0 && carry > 0; i--) {
+            int a = A[i] + carry;
+            A[i] = a % 10 ;
+            carry = a / 10;
+        }
+
+        while ( carry > 0 ) {
+            A.insert(A.begin(), carry%10);
+            carry /= 10;
+        }
+
+        return A;
+    }
+};